Dennis RS/SS series explained

Dennis RS/SS series
Manufacturer:Hestair Dennis
Type:Fire engine
Production:1978-1994
Assembly:Woodbridge, Guildford
Designer:Ogle Design
Body Style:Cab over engine
Related:
Engine:
  • Perkins V8-540
  • Perkins TV8-540
  • Perkins V8-640
  • Perkins T6.354.4
  • Perkins Phaser
  • Cummins 6CT
  • Cummins 6CTA
Transmission:
  • Turner T5-400 five-speed manual
  • ZF S6-65 manual
  • Allison MT643 automatic
  • ZF 5HP500 automatic
Weight:[1]
Successor:
Sp:uk

The Dennis RS/SS series was a range of fire engine chassis built by Hestair Dennis (later Dennis Specialist Vehicles), produced from 1978 until the early 1990s.

Features

Internally codenamed Retained, Steel, the Dennis RS series was first launched in 1979, initially not offered with a tilting cab due to a belief that few fire stations at the time could accommodate a tilting cab. A lower-cost alternative named the Standard Specification, or SS series, was launched shortly afterwards, however at the request of the London Fire Brigade, this would be fitted with a tilting front cab as standard to improve ease of maintenance. The all-steel cab, designed by Ogle Design,[2] replaced the older fibreglass and wood construction of the previous appliances it succeeded, such as the Dennis D and Dennis R, increasing the strength of the cab overall in the event of a collision.

The first of the Dennis RS/SS fire appliances were fitted with Perkins V8 diesel engines, either the V8-540 or the V8-640, with or without turbochargers; by 1987, the RS and SS could be specified with Cummins C-series engines.[3] Early appliances were bodied in-house by Dennis at their Woodbridge factory, but when in-house fire engine bodying was discontinued in 1985, the bodying of the Dennis RS/SS series and derivative products was outsourced to other coachbuilders, primarily to Carmichael Fire.[4] The RS could also be fitted with a variety of bodies by other coachbuilders including HCB Angus,[5] Fulton Wylie and Saxon Specialist Vehicles.

Over 1,750 Dennis RS/SS fire engines would be produced, being sold to nearly all fire brigades across the United Kingdom as well as being exported to various fire brigades worldwide.[6] As the appliances aged, RS and SS series appliances were known to suffer from corrosion particularly around the cab doors, nicknamed "Dennis Disease" by mechanics.

Variants

All chassis came with a choice of a 500gpm or 1,000gpm two-stage Godiva fire pump, depending on application, and a 400impgal emergency water tank.

Significant operators

United Kingdom

Republic of Ireland

Elsewhere

Notes and References

  1. Book: Goundry, Andy. Dennis Buses and Other Vehicles. 11 August 2021. 23 March 2020. Crowood. 978-1-78500-708-8. 106–108.
  2. . 3 December 1983 . If it's a handsome cab, chances are it's Ogle's . . Temple Press . 20 July 2021.
  3. . 22 June 1979 . Hestair launch new custom fire-engine . Commercial Motor . Temple Press . 20 July 2021.
  4. . 23 March 1985 . Dennis moves . Commercial Motor . Temple Press . 10 August 2021.
  5. Book: Fisher, Aidan. HCB Angus Fire Engine Builders. 15 April 2012. Amberley Publishing Limited. 978-1-4456-1119-8. 9 August 2021. ...during the 1980s some 40 DS and RS chassis were bodied by [Angus], mostly as water tender ladders..
  6. Book: Baker, Eddie. Fire Engines. 10 August 2021. 23 August 2018. Bloomsbury Publishing. 978-1-78442-299-8.
  7. . 17 August 1989 . £1m Dennis order . Commercial Motor . Temple Press . 20 July 2021.
  8. . 21 August 1982 . Skidchek goes East . Commercial Motor . Temple Press. 20 July 2021.